I probably shouldn't have mentioned batteries at all considering that we're comparing hydrogen generation technologies. But the review I found shows cycle life

I probably shouldn't have mentioned batteries at all considering that we're comparing hydrogen generation technologies. But the review I found shows cycle life is variable in existing commercial batteries, and generally not much higher than 2000: https://www.nature.com/articles/s41560-019-0356-8 https://www.nature.com/articles/s41560-019-0356-8 The interest in hydrogen is for thermal processes (cement, alumina) and weight-sensitive applications as far as I can see. For electricity storage the fuel cell efficiency is prohibitive.